The present invention relates to vehicle powertrain driveshafts, and particularly driveshafts of the type interconnecting a power transmission and a wheeled drive axle. In many motorized vehicles, it is commonplace to provide an articulated driveline between the engine power transmission, mounted to the vehicle chassis frame or body structure, with a driveshaft having swiveled or universal joints therein for permitting the driveshaft to flex with movement of the wheel drive axle. In such vehicle drivelines, and particularly heavy duty over-the-road trucks, it has been found desirable and advantageous for weight saving to form the drive shaft of relatively thin wall, high-strength premium material such as graphite impregnated composite material. When such materials are employed for the driveshaft, it is extremely costly to replace the driveshaft in the event that there is a failure of the driveshaft. One particularly common type of failure of the driveshaft is that of torsional failure resulting from improper clutch engagement.
It has thus been desired to provide a torque fuse in a vehicle driveline ahead of the driveshaft, or at the transmission output to protect the vehicle from torsional driveshaft failure under heavy service loads.
It has also been desired to provide a torque limiting fuse in the vehicle driveline to protect the driveshaft and to make such a provision without the need for any significant alterations to the construction and manufacture of the vehicle transmission and driveshaft. It has also been desired to enable such a torque fuse to be readily replaced in the field with only minor disassembly of the transmission or drive shaft and to be originally installed without modification of the transmission.